Steam-boiler-tube retarder.



-K. TOWNSEND.

STEAM BOILER TUBE RETARDER.

. 4APPLICATION FILED Au a.21. 1915.

Llj, .Patenfed Mar. 7, 1916.

2 SHEETS-'SHEE l.

K. TOWNSEND.

STEAM BOILER TUBE RETARDER. APPLICATION FILED AuG.21. |915.

' Patentd Mar. 7;, 1916.

2 SHEETS-SHEET 2 KNOWLSON TOWNSEND, 0F SAN FRANCISCO, CALIFORNIA..

Specification of Letters Patent.

STEAM-BOILER-TUBE RTARDER.

Patented Mar. 7, 191.6.

Application levd August 21, 1915. Serial No. 46,637.

v introduced into the said Hue tubes for retarding or slowing the progress of the comy bustion 'gases through the tube in such a manner as to cause the said gases to develop their heat units in passing through and'con- -tacting with the tube walls morev than is vthe case where retarders are not used.

The object of my invention is to provide.

a retarding means of the general character stated, which, when in operative connection with the tube can be readily adjusted for reducing the area of the tube, from the maximum down to one-half, more or less, for slowing the combustion gases as they pass through the tube, to thereby obtain the greater absorption of the heat units due to the increased time contact ofthe hot gases with the walls of the tube.

IAnother and essential object of my invention is to provide a retarding means or device as stated, of a very simple and inexpensive construction and so designed that v when inserted inthe tube it may be readily 'adjusted for reducing .the Hue area, 'as desired, without renewing or removing it from the tube.

Further my invention provides for making my improved form of retarder 'out of the conventional form of retarders, preferably the common twisted retarder, now in general use.

With other objects in view, all of which will be hereinafter fully explained, .my improved boiler tube retarder embodies the peculiar features of construction and novel.v

portion of a single Hue tube with my retarder in place, the same being shown as adjusted all the way in the tube for cutting specifically is a similar view that shows the retarder as projected out beyond the tube outlet for cutting down less than one-half of the tube area. Figs. 3 and 4 are'end views of the retarder and the tube, arrangement shown in Figs. 1 and 2. Fig. 5 is a longitudinal section of a tube -with a slightly modified form of my retarder operatively connected therewith. Fig. 6 is a similar view. of a further modification hereinafter referred to. Fig. 7 is a detail view of one end of the ordinary twisted retarder, showing the manner in which the retarding prongs are formed thereon. Fig. 8 is a diagrammatic, longitudinal`l section of a steam boiler with my improved construction of retarders applied for use. My improved boiler tube retarder is adapted for either marine or stationary engines, but mostly for use in boilers using oil for fuel. v v

In carrying out my invention, I shape up lthe retarder, preferably by taking the common type of twisted retarder as used now, and form, by sawing or otherwise, two cuts 2 in one end 1 thereof, parallel with each other and equally spaced apart.

When the retarder is intended for cutting down the Hue area to the maximum amount, say one-half of the normal area, the said retarder is inserted into the outlet end of thel tube 3, up to the point where the cuts 2 begin, and .after it is thus positioned the three prongs 4a, 4-4 formed by cutting the end of the retarder as stated, arebent back at right angles to the body of the retarder, the l.

bustion of the gases as they pass through they tube.

retarder with long prongs of uniform widths, and of bendable material as shown, the said prong portions can be again bent between their ends to form prong Hngers 5, the said fingers being bent inwardly so as to come up against the tube sheet 6 as is shown in Fig. 2, it being understood that the the area of the tube into one-half. Fig. 2 greater thelength of the said lingers 5, the

By reason of forming the outer end of the farther out from the tube outlet the retarder is-projected, and hence the area is increased above one-half in accordance to the position of the said outer end of the retarder. 'Y

If,4at any time, it is desired to reduce the tube area more than one-half, the retarder may be 'formed,by punching or otherwise,

'with one or more supplemental prongs 8 as shown in Fig. 6, but such supplemental prongs are not essential since to reduce the area of the tube to one-half would be enough.

lf the retarders, when short, have a tendency to Work out of the tube, they can be ymade with sWaged portions9, formed by striking the retarder at its opposite edges with the peen of a .hammer to provide forv holding the retarder in a. tight frictional contact with .the flue as is clearly shown in Fig. 5.

From the foregoing description taken in connection with the drawings the complete Y, arrangement, the manner of using, and the the outer end of vthe said strip having a central prong like portion bent'in one direction at right angles to the strip and another pair of prongs, one at eacli side of the central prong and bent in the opposite direction, the said bent prongs formingclosure means for partly shutting 0E the flue outlet.

3. ln a boiler, the combination of a Hue tube and retarder, `the said retarder co'mprising a metal strip insertible into the Hue, the outer end `of the said strip having a central prong like portion bent in one direction at right angles to the strip and a pair of prongs, one at each side of the central prong and bent in the opposite direction, the said bent prongs forming closure means for partly shutting ofi' the flue outlet, the said prongs having end members bent inwardly at right angles to the body of the prongs to produce abutting members adapted for resting against the flue sheet of the boiler when the retarder is pushed home into the flue.

KNOWLSQN TOWN SEND. 

